1. Field of the Invention
This invention relates to hybridoma cell lines and monoclonal antibodies produced therefrom which may be used to detect salinomycin, particularly in animal tissues and feeds.
2. Description of the Prior Art
The polyether ionophores are a major class of antimicrobials extensively used in agriculture as coccidiostats. Of these ionophoric anticoccidials, salinomycin has gained widespread acceptance, especially in the poultry industry, and has been marketed in all of the poultry producing countries of the world. In the United States, salinomycin is currently the most widely used anticoccidial in agriculture and the broiler industry.
Although salinomycin can be beneficial in broiler production when used properly, the agent is toxic and has a narrow margin of safety when given to chickens or other animals. Generally salinomycin is added to poultry feed as the free acid or its sodium salt at levels ranging fresh 44 to 66 ppm. When fed at higher than recommended levels, or when administered to sensitive animal species, salinomycin toxicosis can occur. For these reasons, an accurate, precise, and rapid method to analyze salinomycin is required.
Analysis of salinomycin in feeds or tissues has utilized bioassays (Official Methods of Analysis, 14th edition, AOAC, Arlington, Va., secs 1984, 42.266-42.270), thin-layer chromatography (Vanderkop and MacNeil, 1990, J. Chromatog., 508:386-390), and normal or reverse-phase HPLC using poet column derivatization with vanillin (Blanchflower et al., 1985, Analysy., 110:1283-1287; Martinez and Shimoda, 1986, J. Assoc. Off. Anal. Chem., 69:637-641; and LaPointe and Cohen, 1988, J. Assoc. Off. Anal. Chem. 71:480-484). However, most of these quantitative methods have significant disadvantages limiting their utility.
Immunoassay methods are rapidly gaining acceptance for the screening and quantification of a number of agricultural chemicals (Hammock and Mumma, In: Recent Advances in Pesticides: Analytical Methodology 1987, Harvey and Zweig Eds., ACS Symposium Series, American Chemical Society, Washington, D.C., 1980, pp. 321-352; Grierson et al., 1991, J. Agric. Food Chem, 39:2327-2331; and Shelby et al., 1992, J. Agric. Food Chem., 40:1090-1092). Miller et al. (1986, Hybridoma 5:353-360) produced monoclonal antibodies to salinomycin for use in an enzyme-linked immosorbent assay (ELISA). The immunogen used to produce the hybridoma cell lines was prepared by linkage of salinomycin to a carrier protein through a succinate moiety attached at the C-20 of the salinomycin molecule. The resultant monoclonal antibodies were reported sensitive to 50 ng of salinomycin per well.